MISCELLANY. 



761 



nearer to the eye than ten inches at least. 

 Besides this, the book ought to be raised 

 20 for writing, and about 40 for reading. 



Ordinarily, minor considerations, such 

 as the most compact disposition of the 

 seats, or placing the pupils so that the 

 teacher may the most readily look into 

 their faces, govern the arrangements of the 

 class-room, and, when any attention is paid 

 to the matter of light, it is often to the 

 detriment rather than the benefit of the 

 class. For example : one of the rules laid 

 down by the Educational Department in 

 London, for the guidance of architects, is, 

 that " the windows should be so placed 

 that a full light should fall upon the faces 

 both of the teachers and the children." 

 Light coming from the right hand is not so 

 good as that from the left, because the 

 shadow of the hand falls upon that part of 

 the paper at which we are looking. Light 

 from behind is still worse, because the head 

 and upper part of the body throw a shadow 

 on the book or paper; but the light that 

 comes from the front, and falls on the face, 

 is by far the worst of all ; for it not only 

 defeats the object desired illuminating the 

 faces of the children but is most hurtful 

 to the eye. Instinctively desirous of avoid- 

 ing the unpleasantness of the full glare, 

 the children will assume all sorts of posi- 

 tions, which turn their faces from the mas- 

 ter. In reading, they turn the head round 

 the vertical axis, generally toward the right, 

 in order to let the light fall on the book, 

 which, when held straight before them, is 

 completely in shadow ; while, in writing or 

 reading (the book being on the table), they 

 bend their heads as low as possible, in or- 

 der to shade their eyes by the projection of 

 the forehead. 



The best light for the school-room is from 

 above ; but, when this cannot be obtained, 

 the desks should be so arranged, in connec- 

 tion with the windows, that the light shall 

 fall upon the book or paper from the left. 



"Where light from gas or other artificial 

 source is used for evening work, it should 

 bo made as steady as possible, and the 

 lights so placed that they will not come op- 

 posite the eye, as in this situation they are 

 dazzling and injurious. Ground-glass globes 

 ought not to be used, for, though valuable 

 in an ordinary room, where they tend to 



diffuse the light more equally, they give an 

 indistinct light for work, and thus put a 

 greater strain upon the eye. And, for the 

 same reason, ground or ribbed glass should 

 not be employed for the lower portions of 

 windows, as the optical effect of such glass 

 in that position is decidedly hurtful. 



Jnte. This remarkable fibre, which 

 formerly was only used for the coarsest 

 purposes, has of late become invaluable. 

 It makes a serviceable substitute for hair 

 in chignons, and is now used extensively 

 as a " mix " in silk. Owing to its kindly way 

 of taking the dye, and the gloss which it 

 sustains, a large quantity can be used in 

 silk, and yet defy detection, except by an 

 expert. It is, in consequence, highly desir- 

 able that it should be produced in our 

 country, if possible. Some experiments by 

 agriculturists are under way, which seem to 

 promise success. Mr. F. T. D. Lacroix, of 

 New Iberia County, Louisiana, has, on his 

 plantation, several rows of the jute-plant, 

 the seed of which was sent to him by the 

 Department of Agriculture. The plants 

 are very vigorous, and the indications are 

 that jute will thrive in that climate. It 

 bears some resemblance to flax in appear- 

 ance, as it is said to in fibre. 



A City's Waste. Mr. Lepmann, direc- 

 tor of the Central Trial Station, in Bavaria, 

 speaks thus of the loss of fertilizers in 

 Munich, a city of 177,000 inhabitants. He 

 makes the sum of fertilizing elements 

 wasted in the human excrements of the 

 city for one year, 1, 857,714 pounds of ni- 

 trogen, of which the commercial value is 

 866,934 gulden; 611,054 pounds of phos- 

 phoric acid, value 122,210 gulden ; 372,375 

 pounds of potash, value 49,650 gulden ; 

 total value 1,038,794 gulden, equal to about 

 $500,000. This sum would be still further 

 increased by adding to it the value of the 

 humus-forming constituents of the excre- 

 ments wasted. To make up fcr that waste, 

 he states that the amount of guano fur- 

 nished by Peru yearly for the German 

 fields is about 1,000,000 cwt. 



Mr. Lepmann states that Germany now 

 possesses a system by which he is confident 

 this enormous waste may be entirely pre- 

 vented, called there the Tonnen (barrel) 



